Kernel parameters required for Oracle 10g with Serviceguard.

[Srikanth Arunachalam]

Hi,

We have the following configuration :-
HP-UX 11iv2,Oracle10gRel2, serviceguard 11.16 for our system configuration. We have good high RAM been placed for different systems as well. I have the following queries with regards to the kernel parameters.

(1) Are there any specific kernel parameters that we need to change on HP-UX, apart from the recommendations given from Oracle site. For example, dbc_max_pct, nproc and nfile. The oracle has recommended value of nfile as 15*nproc+2048 and nproc as 4096 already.Do we need to modify any further. Pls.note that our application is OLTP based and will have too many database hits on it.

Current default value of dbc_max_pct is 50 and
bufpages parameter is not set.I understand that dbc_max_pct dictate how much of the main memory that should be used for file-system buffers. Since, Oracle10g MMON process is capable of handling the memory efficiently of itself, should we reduce the size of this kernel parameter.

Are there any more/any other kernel parameters that require changes apart from what has been specified below.
ksi_alloc_max (nproc*8)
executable_stack 0
max_thread_proc 1024
maxdsiz 1073741824 (1 GB)
maxdsiz_64bit 2147483648 (2 GB)
maxssiz 134217728 (128 MB)
maxssiz_64bit 1073741824 (1 GB)
maxuprc ((nproc*9)/10)
msgmap (msgtql+2)
msgmni (nproc)
msgseg 32767
msgtql (nproc)
ncsize (ninode+1024)
nfile (15*nproc+2048)
nflocks (nproc)
ninode (8*nproc+2048)
nkthread (((nproc*7)/4)+16)
nproc 4096
semmni (nproc)
semmns (semmni*2)
semmnu (nproc-4)
semvmx 32767
shmmax The size of physical memory or 1073741824
shmmni 512
shmseg 120
vps_ceiling 64

[Steven E. Protter · Accepted solution]

Shalom,

Actually you look pretty good here. I've got some old kernels for oracle posted for ITRC and you have most things covered.

Change maxuprc to a numer without a formula. It should be a miminum of 200, perhaps 300 if you run a lot of instances. It controls how many processes one user can have at time. Adjust it based on how many instances.

I'd push up nproc higher if you have a lot of instances running.

Note that shmmax will ignore figures above 25% of memory, which HP-UX defines as swap plus ram. Yet the oracle install blindly insists shmmax must be equal to physical memory. You have to satisfy oracle to even get it to install.

I think shmseg is too low. Shared memory segments should be higher because oracle doesn't always take shared memory in huge chunks, sometimes it takes it in lots of smaller chunks.

SEP
sEP

[Darrel Louis]

Hi,

Check the following link:
http://www.spec.org/jAppServer2004/results/res2006q1/jAppServer2004-20060214-00027.html
See the following Best practices document
http://h21007.www2.hp.com/dspp/files/unprotected/database/HP3KOracle.ppt



For HP-UX IA64, apply the following patches:
PHSS_32502
PHSS_31087
PHNE_32055 (Required for NFS certification)
PHCO_32426 (A kernel panic patch for bug JAGaf61327)

For HP-UX PA-RISC, apply the following patches:
PHNE_32055 (Required for NFS certification)
PHSS_32765

Also see attachment.

GoodLuck

Darrel